For as long as I can remember I have been getting a pink/red irritation and itch where my back meets my butcrack. It goes down maybe two inches. Could this be a form of athletes foot/jock itch? Would it be common for it to appear on my butt crack? I can i treat it and even better, prevent it?!

Dandruff shampoos are antifungal. Try buying a bottle of shampoo like Nizoral or Selsyn (not the tar stuff) and use it like a bodywash for a week or so, see if it helps. There are a couple brands of "gym soap" that are antifungal, though they're harder to find.